What are the risks of regrowth and treatment options for persistent/recurrent NFAs?
The long-term risk of NFA recurrence, after TSS, is estimated to be 33% to 47% and 6% to 16% for patients with, and without, radiographic evidence of residual tumors, respectively, on 3-month post-TSS imaging. Risk factors for regrowth include large/invasive tumors, cavernous sinus/bony/dural involvement, and silent or plurihormonal NFAs. The role of proliferation markers on pathology analyses (e.g., Ki-67, pituitary tumor-transforming gene) for predicting adenoma recurrence is not currently well defined.
For recurrent/persistent tumors, repeat TSS can be considered in select cases where there is radiologic evidence for a surgically-accessible sellar tumor, particularly if associated with mass effects. In general, with each subsequent neurosurgery, the likelihood for gross total resection decreases, and the risk of postsurgical complications increases. Lastly, in nonsurgical cases, radiation therapy is advised when the pituitary tumor remnants are growing significantly or are symptomatic.